The modern era of video slot machines has allowed manufacturers to use virtual reel strips, rather than traditional mechanical reel strips.
The operation of these reel strips are such that a machine picks a spot on the pre-determined order of symbols and displays on the screen that symbol and one symbol above and one symbol below, presenting three rows for the player to view. There are a fixed set of reel strips for a certain bet configuration. Some products change the reel strips during a bonus (but that set remains the same), some have a new set of reel strips in each game of a feature to make one symbol more prevalent (there will be consistency in the changes), and some games change the reel strips depending on the bet configuration picked by the player.
The “243 way” concept pays players according to symbols appearing anywhere on the reels rather than on a pre-determined line. This is also referred to as a scatter pay, where the appearance of specific symbols in any distribution on the displayed frames within the screen can constitute a winning outcome. The “243 way” refers to a 5×3 reel configuration with 243 possible ways of winning (3 to the power of 5). To bet fewer lines, players can play fewer ways. An 81 way pay corresponds to 3 to the power of 4, and a 27 way pay corresponds to 3 to the power of 3. To mathematically implement this, there are different reel strips for each bet configuration option made available to the player.
There are numerous ways in which the probability of outcomes in slot-type and video-type gaming systems are controlled (referred to herein as “slot games” unless distinguished in discussions as reel games or video games specifically). The ways in which probabilities are controlled must be acceptable to gaming jurisdictions and approved by the various jurisdictions. One well-established control of outcomes is taught by U.S. Pat. No. 4,448,419 to Telnaes in which a gaming machine of the type utilizing rotating reels (16) which carry a plurality of indicia on the periphery, a brake (19) to stop the reels at a selected position and a random number generator for selecting the reel stopping position. Numbers are assigned to the reel stopping positions and entered into the random number generator (41), with each number being entered one or more times to control the payout odds of each particular stopping position being selected, thereby enabling any odds to be set without changing the physical characteristics of the machine. The technology is also directly translatable to video systems in which the outcome or probabilities are also weighted by random number generators.
Similarly, but in a uniquely different manner, U.S. Pat. Nos. 6,117,009 and 6,159,096 to Yoseloff teach a method of configuring a video output gaming device to randomly generate game outcomes. The method includes the steps of selecting a set of game symbols, assigning a probability of occurrence to each symbol, selecting a plurality of outcome templates, each template comprising X variables, selecting a probability of occurrence for each outcome template, assigning a subset of symbols from the set of game symbols to each template for filling the positions, defining payouts for selected outcomes, and configuring a video output gaming device, which randomly selects a template, randomly selects a symbol for each variable in the template from the subset of game symbols assigned to the selected template, randomly fills at least a portion of the positions in the template and displays the outcome on a video output display. A video output gaming device is programmed to randomly select a template, randomly select symbols to define the variables and randomly display the selected symbols.
U.S. Pat. No. 6,095,921 to Walker et al. discloses a gaming device and method for operating the gaming device. The gaming device initiates a paid play, and determines an outcome of the play. The outcome is visually displayed using at least two graphical displays. The graphical displays comprise a first and second visual continuum, without discrete reel stops. The outcome is represented by the relative positions of the first and second visual continuums. The outcome may also be based on the relative position of the first and second continuums to a payline. A payout corresponding to the outcome is determined by the device and is awarded to the player.
U.S. Pat. No. 3,645,531 to Wright provides a horse-race wagering device in which a gaming machine comprises a projector for projecting an endless film of horse races. The film is divided into four subframes, a selected one of which is brought to a screen by means of a system of tilting mirrors. The selection of subframe is made at random twice in each race to give unpredictable variations of the race shown; a coin mechanism is provided so that bets can be made and winnings paid out in accordance with the outcome of the race.
U.S. Pat. No. 5,980,384 to Barrie describes a gaming apparatus and method in which there is a primary game and a secondary game that are dynamically linked, and the primary game can be won independently of the secondary game. The primary game may be won on each play of the game, and the secondary game may be won over a plurality of plays of the primary game. Primary game symbols appearing during plays of the primary game may cause: (i) movement of primary game symbols to secondary game display positions; (ii) primary game symbols directing play options of secondary game symbols; (iii) changing the options open to the player in his or her attempt to win the secondary game; (iv) symbols in the primary game being used as soft buttons to affect movement of game symbols from the primary game to the secondary game, and between symbol display positions in the secondary game; and (v) secondary game symbols persisting to subsequent plays of the primary game to help the player to win at the secondary game. Multiple images are shown associated with the positions of single frames.
Reissued U.S. Pat. No. RE35,188 to Howard discloses a reel for a fruit machine, a reel having standard symbols or fruit, on which secondary symbols, for example, numbers, are superimposed. The reel has a first, inner strip on which the standard symbols appear, the strip being carried by a reel drum. The secondary symbols appear on a second, outer strip glued to the first strip. The second strip is mostly transparent so that the standard symbols may be viewed with the secondary symbols superimposed on them.
Other games have a set of reel strips in the main game, and once free games are triggered, change to another set to increase the chance of players winning. This is done by increasing the number of higher paying symbols in proportion to lower paying symbols. This method is set and predetermined by the machine manufacturer.
A further game format may offer a free game bonus where more of the substitute symbols appear on the reels as each game continues. In these cases, one more symbol is added to the reel for each game. This means a new reel strip configuration for each free game.
Any reference herein to known prior art does not, unless the contrary indication appears, constitute an admission that such prior art is commonly known by those skilled in the art to which the invention relates at the priority date of this application. All references cited herein are incorporated by reference in their entirety for their technical disclosure.